Stir the chicken pieces, garlic, ginger, lemon juice, brown sugar, coriander, cumin, turmeric, paprika, onion powder, salt, and pepper in a large bowl until the brown sugar dissolves and the chicken pieces are evenly coated. Cover and refrigerate for at least 1 hour, stirring once.
Divide the chicken cubes among eight 6-inch bamboo skewers, threading about four pieces on each skewer and leaving a little room between each piece.
Pour the broth into the insert set in a 5-, 6-, or 8-quart Instant Pot. Set a pressure- and food-safe rack or trivet in the insert. Pile the skewers on the rack and lock the lid on the pot.
Set your Instant Pot to Pressure Cook or Manual on High Pressure and cook for 12 minutes. When the pot has finished cooking, use the quick-release method to bring the pressure back to normal. Unlatch the lid and open the cooker. Use kitchen tongs to transfer the skewers to a serving platter. Remove the rack or trivet from the pot.
For the MAX model: Set the pot for Pressure Cook on MAX for 10 minutes.
When the pot has finished cooking, use the quick-release method to bring the pressure back to normal. Unlatch the lid and open the cooker. Use kitchen tongs to transfer the skewers to a serving platter. Remove the rack or trivet from the pot.
Press Sauté and set it for High for 10 minutes.
Stir the liquid in the insert as it comes to a full simmer. Cook, stirring occasionally, until it’s reduced to about a third of the volume before you began simmering (that is, until it’s about 1/2 cup), about 8 minutes.
Turn off the heat and whisk in the yogurt until smooth. Use hot pads or silicone baking mitts to pick up the (hot!) insert and drizzle the sauce over the kebabs, pouring any extra sauce to be served on the side in a bowl. Sprinkle fresh cilantro over kebabs as a garnish.